Evaluation instrument for phosphate glass dosimeter

Abstract

A device for evaluating the exposure of a phosphate glass dosimeter to ioing radiation by effecting differential scanning of the dosimeter glass with light radiation, including a member for holding the glass stationary, a device for supplying a single beam of light for effecting the evaluation; and a scanning system composed of an element defining a pivotal, elongated slit, two rotatable mirrors and two stationary mirrors arranged in the path of the single beam and operable for causing the beam to scan the glass selectively along any one of three coordinates.

What is claimed is: 
     
       1. In a device for evaluating the state of a phosphate glass dosimeter by effecting differential scanning of the dosimeter glass with light radiation, the improvement comprising: means for holding the glass stationary; means supplying a single beam of light for effecting the evaluation; and scanning means composed of an element defining a pivotal, elongated slit, two rotatable mirrors and two stationary mirrors arranged in the path of the single beam and operable for causing the beam to scan the glass selectively along any one of three coordinates. 
     
     
       2. A device as defined in claim 1 wherein said element defining a slit is located at a point where the path of the beam is stationary, the axes of rotation of said two rotatable mirrors are perpendicular to one another, and said scanning means operate to maintain one of said rotatable mirrors fixed during scanning along any one coordinate. 
     
     
       3. A device as defined in claim 1 or 2 wherein at least one of said rotatable mirrors is selectively positionable for causing said scanning means to deflect the axis of the single beam through a total angle of 270° or 360° between said element defining a slit and the dosimeter glass. 
     
     
       4. A device as defined in claim 1 or 2 further comprising a radiation detector fixedly disposed relative to the glass and is spaced therefrom in a direction perpendicular to the direction of impingement of the single beam on the glass. 
     
     
       5. A device as defined in claim 1 or 2 wherein the coordinates are mutually orthogonal, the glass is in the form of a parallelepiped, and scanning along each coordinate is perpendicular to one surface of the parallelepiped. 
     
     
       6. A device as defined in claim 1 wherein said means for holding the glass stationary comprise a resilient element pressing the glass against a stationary surface, such that the position of two outer edges of the glass is accurately defined. 
     
     
       7. A device as defined in claim 6 wherein the resilient element is a tongue. 
     
     
       8. A device as defined in claim 6 wherein the resilient element is a wire. 
     
     
       9. A device as defined in claim 1 in combination with an adjusting cube surrounding a glass sample and provided with adjusting bores for adjusting said scanning means. 
     
     
       10. A device as defined in claim 1 wherein said element defining a slit is pivotal about an axis parallel to that of the beam and is formed to cause the single beam to have, at the location which it impinges on the glass, a rectangular cross section the narrow dimension of which extends in the scanning direction and is substantially smaller than the dimension of the glass in the scanning direction.